Dr. Dietrich, who has extensive experience in the fields of developmental assessment and environmental neuro-epidemiology will direct the Neurobehavioral Core. Dr. Douglas Ris will assist Dr. Dietrich, an experienced researcher and board certified clinical neuropsychologist. The Neurobehavioral Core will provide services to Projects 1 (Cohort Study of Prevalent Toxicants), Project 4 (Early Exposure to Lead and Antisocial Behavior and Criminality in Young Adults), and Project 5 (Lead Exposure and Brain Functioning). The functions of the Neurobehavioral Core fall into the categories of: a) recruitment and training, b) data quality assurance, c) data monitoring (safety), and d) data analysis and interpretation. Some of these functions overlap with activities within the individual projects and other cores. The principal focus of this core, however, will be to support the recruitment and training of examiners, test administration, and interpretation of neuropsycholgical outcome measures as they apply to the aforementioned projects.